1. Field of the Invention
The present invention generally relates to removal of fence posts and, more particularly, is concerned with a post pulling apparatus with interchangeable working heads for pulling and removing different types of fence posts.
2. Description of the Prior Art
Different types of fence posts are employed in many different applications along highways, on farms and ranches, and at construction sites. Most types of posts are relatively easy to install but ordinarily are more difficult to remove, requiring the expenditure of more time and effort in their removal than installation.
In an attempt to reduce this difficulty, many different apparatuses have been proposed in the prior art for pulling and removing posts. Exemplary prior art apparatuses are described and illustrated in Sanders U.S. Pat. No. (2,377,652), Lundgren et al (2,777,726), Kohorst (2,826,392), Michalak (2,994,510), King (3,779,516), Skinner (3,991,976), Boardman (4,040,601), Parker (4,161,310), Keller (4,726,565) and Hoff (4,738,433). Many of these prior art apparatuses, such as the ones disclosed by the Sanders, Lundgren et al, Kohorst, Michalak, Parker, Keller and Hoff patents, employ an upright support member having a base resting on the ground and a lever arm pivotally mounted to the upper end of the support member, and a working head pivotally attached to the end of the lever arm and coupled about the post to be pulled such that by actuating the lever arm in a "jacking" type motion the post is lifted and dislodged via the working head from the ground.
These prior art apparatuses probably operate satisfactorily and generally achieve the intended result of pulling posts. However, many are limited in the sense that they employ only a single working head adapted for pulling a specific type of post, whereas, for example on farms and ranches, typically different types of posts will be used to fulfill different fencing requirements and needs. Given the limitation of prior art apparatuses, a separate entire apparatus would have to be available to use with each different type of post.
Consequently, a need still exists for a post pulling apparatus which will effectively handle the different types of posts typically used in fencing applications on farms and ranches, along highways, and at construction sites.